Due to the nature of truck design for carrying certain materials, (i.e. gravel, garbage, large odd shaped objects and the like) there is a need to cover these materials to prevent damage to the materials and to prevent their release onto the highway. These loads, that are placed upon the beds of trailers, require a protective covering. Typically, this protective covering takes the form of sheets of plastic material and/or a canvas material, such as a tarp that are secured to the load and the trailer bed so as to prevent exposure of the load to the elements. The tarp and plastic are secured to the trailer bed so as to prevent flapping or tearing of the plastic from the excessive wind forces that most trailer beds undergo during the course of transporting loads on highway systems.
The tarps and plastic are typically folded or rolled up to conserve space when the tarps and plastic are not in use. The tarps used are generally heavy and quite bulky, making it difficult to cover the load, especially if one person is working alone. Even when multiple people are covering the load it is still a hazardous activity. Generally, the method of tarping has been to place a person on top of the load and to lift the tarp up to the person. The person on top of the load must unfold the tarp and evenly cover the load all while perched on top of the load. This is very dangerous and many accidents have occurred because people have lost their footing and fallen off the load that they were trying to cover.
The trucking industry has responded with three partial solutions to the aforementioned problems. The first is to place fall supports in the places where tarping of the loads is to occur. Fall supports are expensive and should be individualized to each tarper. Further, fall supports do not adequately protect the tarper from being hurt. Although the fall support prevents the person from hitting the ground, when a person strapped to a fall support falls, he falls into free space with no method of controlling his direction or speed. Instances have occurred where a person, strapped to a fall support, has fallen off the load he was tarping and swung into free space. The person then swung back and slammed into the load of the truck that he was tarping and was seriously injured.
The second solution is a mechanized tarp loader. This device hooks to the grommets that are found in typical commercial tarps. The device then pulls the tarp from the ground over the load to the other side of the load. This device does not work for many different kinds of materials, such as sheets of plastic, since the hooks will rip the plastic or the plastic must possess grommets for the hooks to engage. In addition, if the load has sharp edges of any sort, dragging the tarp along the sharp edges will tear the tarp, thereby exposing the load to the elements.
The third solution is the attachment of a crane-like device to the truck to assist with lifting the covering over the load. Two problems still exist with these devices. First, the covering material must be dragged across the load, resulting in damage to the load being covered or the covering itself depending on the nature of these materials. Second, the added expense and added weight to the truck load make these devices less desirable.